Bilby Facts and Figures
Greater Bilby Macrotis lagotis
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The Bilby is the largest member of the family of marsupials called bandicoots.
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The Bilby has a long pointed nose, huge ears and a black tail with a white crest. Bilby fur is soft and silky, mainly pale
blue-grey, sometimes with some fawn on the thighs, and a white or cream underside and feet.
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An adult male Bilby can weight up to 2.5kg, with body length up to 55cm plus a tail of up to 29cm. Females are about
half the size of males.
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The large ears of the Bilby are almost hairless. As well as providing great hearing, they are also believed to help the Bilby
regulate its temperature. Bilby ears are extremely manoeuvrable and can be rotated, held flat against the body, stuck out
perpendicular from the body, and even folded in half.
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The long snout, which is pink and hairless at the tip, gives the Bilby an excellent sense of smell. Many long, dark
whiskers protrude from either side of the snout. The Bilby's tongue is long and slender. Bilbies have 48 teeth, 26 upper
and 22 lower. The upper teeth consist of 5 incisors, 1 canine, 3 premolars and 4 molars on each side. The lower teeth
consist of 3 incisors, 1 canine, 3 premolars and 4 molars on each side.
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Bilbies have poor vision and rely on their strong senses of hearing and smell. Their eyes are black, up to approximately
1cm in diameter, and surrounded by fine black eyelashes.
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Strong forelimbs with long claws make the Bilby a brilliant burrower - they have 5 front digits, the middle 3 being longer
with strong curved claws. Their hind limbs are long and slender with a large “middle toe”, similar to a kangaroo.
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Bilbies live in spiralling burrows which they dig up to 2 metres deep. A Bilby may have up to a dozen burrows.
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The pouch of the female Bilby opens backwards so as not to be filled with dirt while digging. It contains eight nipples
arranged in two facing crescents.
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Bilbies are truly nocturnal. They don't emerge from their burrows until at least an hour after dusk, and retreat at least an
hour before dawn.
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The tail of the Bilby is the same blue-grey colour as the majority of the body along the first few centimetres and is then
black for about half the remaining length and finally white. These three coloured sections of the tail are very distinct. The
tail has a naked spur-like tip which is generally hidden from view beneath the fur.
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The Bilby has a cantering gait, with the hind limbs moving together and the fore limbs moving alternatively when
travelling slowing and together when moving more rapidly. The tail is often carried upright like a banner.
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Bilbies are omnivorous. They eat such things as seeds, spiders, insects and their larvae, bulbs, fruit, fungi and small
animals.
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Bilbies are mostly solitary, but sometimes live in small groups of up to four.
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Bilbies breed throughout the year depending on rainfall and food availability.
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The gestation period of the Bilby, at 14 days, is one of the shortest of all mammals. When conditions are favourable
female Bilbies can produce four litters of up to three Bilbies each every year.
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Young Bilbies are carried in the pouch for approximately 75 days and become independent within about two weeks of
leaving the pouch.
Bilby Distribution Past and Present
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Before European settlement, Bilbies were distributed over approximately 70% of the Australian mainland. Their
range included most of the country west of the Great Dividing Range.
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Presently Bilbies can be found in a small area in south-west Queensland and in isolated colonies spread across parts of
Western Australia and the Northern Territory.
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In the Northern Territory Bilbies live in mulga shrublands and spinifex grasslands in the Tanami Desert. In Western
Australia they are found in the Gibson and Great Sandy Deserts and the Pilbara and Kimberley regions. In
Queensland they inhabit the Mitchell grasslands of the far south-west.
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Because Bilby colonies are so isolated, each colony is vulnerable to disease and inbreeding.
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Bilbies are listed as Vulnerable in Western Australia and the Northern Territory, Endangered in Queensland, and
Extinct in the other mainland states.
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Aboriginal Australians hunted Bilbies for food and for their skins, however this hunting is in no way responsible for
the declining Bilby population.
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Major reasons for the decline in Bilby population and distribution are:
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Loss of habitat. Agricultural activities now extend over most of Australia’s fertile regions, with tree
clearing, crop planting and domestic stock grazing making these areas unsuitable for Bilbies. Altered fire
patterns have also changed the types and abundance of food plants available to Bilbies.
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Hunting and trapping. In the late 18th century Bilbies were hunted for their skins resulting in a large
reduction in their population. Many Bilbies were killed by traps and poison baits intended for rabbits.
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Competition from introduced species. Cattle and sheep eat the same plants as Bilbies, only they eat much
more of them. Rabbits compete for food and burrows with Bilbies. The grazing of cattle, sheep and rabbits
reduces native vegetation cover and prevents natural revegetation.
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Predation from introduced species. Foxes and feral cats prey on Bilbies. Wherever these introduced pests
have spread Bilbies have declined in numbers or disappeared altogether.
Sources:
Frederic Wood Jones. The Mammals of South Australia, part II The
Bandicoots and the Herbivorous Marsupials. 1924.
Peter McRae. The Gentleman of the Inland Plains (article in Wildlife
Australia). 1995.
Tim Flannery. Australia's Vanishing Mammals. 1990.
Raymond Hoser. Endangered Animals of Australia. 1991.
Environment Australia. Bilby Fact Sheet. 1998.
Richard Wells. Australia's Endangered, Vulnerable and Extinct Fauna (CD
ROM). 1996.
Queensland Parks and Wildlife Service.
© 2002